Horse inhales approximately 3.5 liters per second (L/s) of air at rest and a staggering 70 L/s at maximum exertion. To put this in perspective, two industrial-sized vacuum cleaners would be required to generate the 70 L/s of airflow a horse is capable of producing while galloping. Given this tremendous flow rate, the soft tissue structures comprising the equine upper airway experience significantly increased forces during exercise. This difference in resting and exercising forces causes the upper airway tissues to appear anatomically normal at rest, even if they’re functioning abnormally during exercise. To fully diagnose upper airway dysfunction during exercise, veterinarians rely on dynamic endoscopy. This technology has helped veterinarians diagnose upper airway dysfunction during exercise.